Electricity is typically transmitted through overhead power lines supported by utility poles. These utility poles may also support other public utility lines, such as cable lines and telephone lines, and related equipment such as street lights, service lights, transformers, and transmitters. Besides supporting the public utility lines, the utility poles keep the overhead power lines and other electrical lines insulated from the ground and away from the reach of people. Downed poles can pose a hazard to people's safety and nearby property, including electrocution, fire, structural damage to surrounding structures and buildings, and power and utility outage, which can cause lost revenue and imposed fines.
Weather conditions and the ground for supporting a utility pole are factors in the design and construction of the utility pole. Over time, the performance of the utility pole may change. In one example, the age and deteriorating conditions of the pole, such as rot or stress fractures, can impact the deflection of the utility pole during high winds. Over time, the utility poles may fracture or snap when the load on the pole exceeds the structural integrity of the pole. In another example, soil movement at the foundation of the utility pole may cause the pole to tilt and/or shift at its base, which can further cause the utility pole to topple over and/or snap. Some utility poles can experience both pole deterioration and soil or ground movement.
Utility poles are typically inspected periodically to determine to determine their conditions and health status to then evaluate which of the poles need to be repaired or replaced. In some cities, the utility poles are required to be inspected every five years. Inspections of the utility poles are typically conducted when weather conditions permit. This allows inspectors or field technicians to safely inspect the utility poles. For example, inspecting the utility poles during a major windstorm would be unsafe and assessing the pole's condition quite difficult. Thus, a majority conventional inspections occur when the structural pole strength is not stressed or lightly stressed and may not reflect the most accurate data.
In high risk areas, such as in areas of extreme weather conditions or highly populated areas, the frequency of inspections can increase. The frequency between inspections can be driven in part by the sheer number of utility poles, the manpower needed to carry out the inspection, and the costs to inspect each utility pole. Between inspections, many events can occur affecting the utility poles.